Hi folks, i'm from the UK so some of my jargon may seem wierd to you. Please bear with it

Car is a WRX MY97 turbo, import .

Went for my SVA today but failed its emissions test.
The cause :
Tester ran the speed test , passed with flying colours.
After finishing that, he took it 10 yards to the emissions test area.
The Idle would not come down to 600-700, but stayed at 1900.
Would not come down at all, so he failed it as he couldnt carry out the idle test.

Drove it back to my garage, when stopping in traffic idle still the same.

When arriving back at my garage, switched off...then back on
still idling at around 2k.
All going reasonably well until that happened.

For the test i took off the *** centre and Blitz backbox, and put on a standard uk centre cat and peashooter backbox.

Anyone help...please
Glenn

 

I have the same problem... this is the check list for identifying if it is your harness or your idle air control valve (IAC).

http://www.geocities.com/kuleshoff/IAC.htm

Paul

 

Thanks Paul, did this fix yours and what was faulty ?

I have also posted this in another forum on a uk site. and received this reply :

Idle is controled by the idle control valve, sounds as though its stuck, look at the left front of the intercooler, there is a beige coloured moulding held onto the inlet manifold with two screws, this uis the ISC. Mark the position of thye flange to the inlet manifold, remove two screws and the body of the valve will lift off, inside is an armature that should be free to rotate, check it does with no stiction, clean the body and the armature with brake cleaner/degreaser, then reassemble, make sure marks are precisely lined up. Start her up and see what happens, if its still a problem you could have a faulty wiring loom from the valve to the ecu, then you need to beep the cables to check they are intact. if you need to do that come back to me and I will dend you the wiring info to check it with.

BTW a faulty maf is unlikely as this has a hot wire one and the symptoms are failing to idle not idling high.

edited to add check all the pipe connections on and around the manifiold as well, also chack for stuck throttle and that nothing is trapped around it or the cable for that matter.

Many thanks
Glenn

 

Haven't recieved the part... it is a little like chasing a needle in a haystack... the wiring seems okay... on an OBDII car (I'm not sure a UK 97 is OBDII) you get a CEL value of p0508 - low circuit to idle control (or something like that)... I will let you know what the resolution is... I may take mine a part and clean it again... keep in mind that you should buy some make-a-gasket material because the gasket for the valve is unlikely to fit back in place after you remove it... or track down a replacement.

Good luck,
Paul

 

Hi Paul, it was my ICV.
It had to be replaced, tried cleaning it still didn't work quite right.

All ok now tho.

 

Thanks for the update... I believe mine is the same... couldn't find a used part... or a volunteer to verify it was the valve... so just going to bite the bullet and order the part... 257 dollars + shipping... hope I guessed right.

Paul